Attribute management can become quite confusing and this will probably confuse you more.
The best option is to always base all of you file from the same template, so at least you have a fighting chance of keeping the attributes the same for all files.This is not always possible of course and as soon as you amend attributes in one file the others do not update so you instantly have differences.
Sometimes this can be a problem, other times you may not notice anything.
A MOD file should contain only the attribute (layers, line types composites, etc.) that have been used in the MOD file itself.
All other attributes that have not been used will be discarded to keep the MOD file as small as possible.
This is where the problems can start.
The original PLN where you create what will become the module, may have say 50 line types (50 line attributes) - the same applies for all the other attributes as well.
So you create what will be the module and have used only 5 line types.
You save it as a MOD file - it should only have 5 line types in it.
When you open that MOD file it will have those 5 line types as well as the line types from the last file you had open in Archicad - why it does this I don't know.
But if these attributes are different from you main file then any modifications you make to the MOD file, may now contain these different attributes.
I say different, they may be completely familiar to you, but if they have the same names (that is what you see) but different attribute index numbers, the module may change appearance when you merge it into another file.
It is hard to say why you hotlink file is not updating without seeing all the files involved.
Unfortunately you can't open a MOD file in Attribute Manager, so you can't see the attributes (and their index numbers) that have been used.
If you could you could compare them with you other PLN files.
I am not sure this will help with anything.
Just trying to explain it a little but as I said it is a bit hard without seeing the actual problem files.
I wasn't going to post this after writing it, but decided I would anyway just to explain why you see other attributes in your MOD file.
It depends on the file you have open before you open the MOD file.
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